DART 300 Migration Guide Difference Summary
2110291 Rev 1.0 Page 11
3.1.2. Control Lines
The DART 300 does not allow configuration of the DCD and DSR signals; a feature supported in
the DART 200.
Flow control on the DART 300 is through hardware only via RTS/CTS and DTR.
DART 200 DART 300
RTS/CTS
Hardware and software flow
control both supported via AT
command.
Only active in online mode.
Hardware flow control only.
RTS must be asserted to allow
serial communication from the
DART 300 to the host.
DTR must also be asserted to
allow received data state traffic to
flow to the host.
DCD
Configurable to track CDPD
registration state, link established,
or connection established
Asserted while online with an
active session. Not configurable.
DSR
Configurable to track CDPD
registration state, link established,
or connection established
Always on when the modem is
powered up. Not configurable.
DTR
Supports
&D0
, and host activated
escape via
&D1
, and
&D2
.
Hardware debounce is 15μs.
&D0
ignores DTR transitions
1
.
&D1
enters command state
without changing on/off-line
condition.
&D2
hangs up and enters
command state with auto-answer
disabled.
Software polling used to
determine state. No debounce.
DTR must be asserted to allow
received data to flow to the host.
RI Not supported.
Triggered on UDP/TCP mode
connection requests.
Configurable operation in
SLIP/PPP modes.
1
The DART 300 using the
&D0
setting still requires DTR to be asserted in order to pass received
data to the local host.
